Accurate time scales for climate archives from European tree-ring chronologies in the Late Glacial - Extension and consolidation of Swiss and German pine chronologies back to 14000 BP

年轮年表是重要的古环境代用档案，因为全球许多不同地区都有可靠的主年表。其独特的定年精度对古气候学、古生态学、考古学和放射性碳定年等诸多领域的应用产生了重要影响。在这里，我们努力巩固和扩展来自Hohenheim/Zurich的世界上最长的连续树轮宽度年表，该年表目前可追溯到距今12 500年（BP）。2013年，在苏黎世镇发现了256棵松树（此处称为Binz材料），第一次放射性碳定年现在表明时间窗口在14000到11000 BP之间，这意味着填补12500 BP左右晚冰期树木年轮年代学的现有空白的希望很大。如果成功的话，世界上最长的、绝对有日期的、连续的树木年轮记录将延长近两千年，直到大约14000 BP，从而涵盖了一个特别有趣的气候转变，从最后一个冰河期到全新世早期——这一时期的替代证据通常很少。然而，实现这一任务需要瑞士和德国的国际合作，除了树木年代学的环宽度和密度测量外，还将产生相应的高分辨率放射性碳（14C）日期以及稳定同位素（13C和18O）记录。提出的多参数方法不仅将支持和加强通常仅基于环宽度测量的年代学发展过程，而且特别有助于我们对新仙女木期周围晚冰期的古环境理解，在这一时期，快速的气候变化可能为最近的人为变化提供了自然模拟。新的多参数树木年轮档案将允许将2000多年来基于树木年轮的陆地放射性碳校准曲线扩展到冰川晚期，大大提高了考古学家和地球科学的放射性碳定年精度。结合一些现有的海洋放射性碳记录和极地冰芯（10Be, 36Cl）的补充放射性同位素记录，精确和高分辨率的校准曲线还将提供有关太阳活动变化的信息，以及与水文循环快速变化有关的普遍较冷到较暖的假定气候条件转变的趋势和极端情况的证据。此外，树木年轮的年代际至百年代际14C变化将与极地冰芯10Be的镜像进行比较，从而将冰芯时间尺度锚定在树木年轮尺度上。考虑来自同一棵树的高分辨率稳定同位素（13C和18O）将进一步帮助我们捕捉冰川晚期温度和降水变化的全部范围。

Annually resolved and absolutely dated tree-ring chronologies are important paleo-environmental proxy archives, because robust master chronologies are available for many different regions around the globe. The unique dating accuracy has a strong impact on many fields of application, such as paleoclimatology and paleoecology, but also archeology and radiocarbon dating. Here, we strive to consolidate and extend the worldwide longest continuous tree-ring width chronology from Hohenheim/Zurich, which currently reaches back to 12 500 before present (BP). An exceptional discovery of 256 individual pine trees within the town of Zurich in 2013 (herein referred to the Binz material), for which first radiocarbon dates now suggest a time window between 14 000 and 11 000 BP, implies strong hope to fill the existing gaps in the Late Glacial tree-ring chronology around 12 500 BP. If successful, the worldwide longest, absolutely dated and continuous tree-ring record would be extended by almost two millennia until around 14 000 BP, thus covering a particularly interesting climatological transition from the Last Ice Age into the Early Holocene - a period for which proxy evidence is generally scarce. Achieving this task, however, requires joint forces across an international Swiss-German collaboration, which will in addition to the dendrochronological ring width and density measurements also generate corresponding high-resolution radiocarbon (14C) dates as well as stable isotope (13C and 18O) records. The proposed multi-parameter approach will not only support and strengthen the chronology development process typically based on ring width measurements alone, but particularly also our palaeoenvironmental understanding of the Late Glacial period surrounding the Younger Dryas, a period during which rapid climatic shifts likely provide a natural analogue to the most recent anthropogenic change.The new multi-parameter tree-ring archive will allow extending the tree-ring-based terrestrial radiocarbon calibration curve for more than 2 000 years into late glacial times improving considerably radiocarbon dating accuracy for archaeologists and geosciences. In combination with several available marine radiocarbon records and complementary radioisotopic records from polar ice cores (10Be, 36Cl), an precise and highly resolved calibration curve will also provide information about changes of solar activity, as well as evidence for trends and extremes at the putative transition of generally colder to warmer climatic conditions, associated with rapid changes in the hydrological cycle. In addition, decadal to centennial 14C variations in tree-rings will be compared to the mirror image of 10Be in polar ice cores, thus anchoring the ice core time scale to the tree-ring scale. Consideration of the high-resolution stable isotopes (13C and 18O) from the same trees will further help us to capture the full range of late glacial temperature and precipitation variability.